Generally described, computing devices and communication networks facilitate network-based commerce. For example, a user may employ his or her computing device to access a network-based service, such as a retail website, for the purchase of items and services (collectively and individually referred to as “items”) such as music, books, and electronics, just to name a few. These items may be offered for purchase or “listed” on the network-based service. For example, a user may purchase a listed item directly from the network-based service. A user may also purchase a listed item from another source affiliated with the network-based service.
In some instances, a user may be interested in an item not offered by the network-based service or by any affiliated sources, also called an “unlisted” item. For example, the user may search for the item on the network-based service and its affiliated sources, but fail to find the item. Since the user could not find the item on the network-based service, he or she may seek another provider for the item, costing the network-based service and/or its affiliates a potential sale. In another example, the user may be interested in an item offered by the network-based service, but may deem the price too high or deem shipping to take an unacceptably long time, and may take his or her business elsewhere.
Adding unlisted items and/or unlisted sources to the network-based service may mitigate or prevent these outcomes, while advantageously providing users with more items from which to choose and/or lower prices for items. It may be challenging to determine which items interest users, however. For example, the network-based service may not have any purchase history data to determine which items may interest a user. Additionally, it may be difficult to select a source to provide unlisted items, as many sources may offer unlisted items for sale. The network-based service may bear an unacceptably high risk in offering an item through a new source without knowing which items to offer or without knowing which sources may offer interesting items.